Simple Methodology for Estimating the Groundwater Recharge Potential of Rural Ponds and Lakes Using Remote Sensing and GIS Techniques: a Spatiotemporal Case Study of Roorkee Tehsil,India     

Ishita Bhatnagar  Kamal Jain 《Water Resources》2020,47(2):200-210

Water Resources - Groundwater resources are depleting at an alarming rate all over the world. Therefore, ensuring water security is the foremost priority of every nation. This paper presents a...  相似文献   

Assessment of glacier stored water in Karakoram Himalaya using satellite remote sensing and field investigation     

Kamal Kant SINGH  Harendra Singh NEGI  Dhiraj Kumar SINGH 《山地科学学报》2019,(4)

Karakoram Himalaya(KH) has continental climatic conditions and possesses largest concentration of glaciers outside the polar regions. The melt water from these glaciers is a major contributor to the Indus river. In this study, various methods have been used to estimate the ice volume in the Karakoram Range of glaciers such as Coregistration of Optically Sensed Images and Correlation(COSI-Corr) method and Area-Volume relations. Landsat 8 satellite data has been used to generate the ice displacement, velocity and thickness map. Our study for 558 Karakoram glaciers revealed that the average ice thickness in Karakoram is 90 m. Ground Penetrating Radar(GPR) survey has been conducted in one of the KH glacier i.e. Saser La glacier and the collected GPR data is used for the validation of satellite derived thickness map. GPR measured glacier thickness values are found comparable with satellite estimated values with RMSE of 4.3 m. The total ice volume of the Karakoram glaciers is estimated to be 1607±19 km3(1473±17 Gt), which is equivalent to 1473±17 km3 of water equivalent. Present study also covers the analysis of glacier surface displacement, velocity and ice thickness values with reference to glacier mean slope.  相似文献   

Seismic identification of geothermal prospecting in Harrat Rahat,Northern Arabian Shield     

Al-Amri  Abdullah M.  Abdelrahman  Kamal  Mellors  Robert  Harris  David 《Arabian Journal of Geosciences》2020,13(8):1-11

Influenced by mining activities in adjacent coal seams, stresses on rocks surrounding roadway were redistributed, and the roadways in lower coal seam were subjected to the asymmetrical roof falling and roof sagging. Considering stresses effect on the plastic zone around the roadway, numerical models were carried out by FLAC to investigate plastic zone with respect to stress ratio and direction of stresses. The relationship between the properties of surrounding rock and plastic zone boundary was also investigated by another numerical model and analytical study, whereby the tailgate stability of panel 30,501 in Tashan coal mine was implemented. It is shown that the rocks surrounding a roadway in the lower coal seam were subjected to unequal stresses, and the principal stress direction was deflected from the original direction. High stresses and big stress ratio can produce butterfly-shaped or X-shaped plastic zone. The direction of stresses was deflected, causing the plastic zone around the roadway to be transferred from the shoulder to the roof of the roadway. Consequently, asymmetrical stresses produce asymmetrical plastic zone. On this basis, the tailgate should be assigned conditions of the stresses and stress ratio at a low level. In this way, the tailgate was arranged at the position where the horizontal distance from the roadway in the lower seam to the centre line of the coal pillar in the upper seam (x) is 52.5 m, and was stable relatively.  相似文献   

Near-surface foundation level assessment from seismic measurements: a case study of north Jeddah City,Saudi Arabia     

Mogren  Saad  Aldahri  Maher  Abdelrahman  Kamal  Zahran  Hani 《Arabian Journal of Geosciences》2020,13(5):1-22

In this study, a comprehensive assessment on the generation mechanism, distribution characteristics, and extension rules of structure cracks was conducted by in situ monitoring and field investigation in the Chengchao Iron Mine. Structure cracks are affected by many factors, e.g., surface deformation, structure strength, occurrence position, and machine vibration. They initially occur in a structure when the strength of the structure is not enough to resist the inner strain as surface deformation increases. In contrast, increases in width and length of structure crack exert stress release in the structure and thus decrease structure deformation surrounding the crack. A great ground crack may adversely aggravate structure cracking and release the stress of surrounding rock masses. In addition, micro cracks in rock masses provide favorable conditions for the generation and extension of cracks, resulting that cracks occur in shaft walls more easily and extend towards the deeper. The initial distribution of cracks is generally consistent with such micro cracks. Subsequently, cracks in deep rock masses will extend along the strike of the mined-out area as surface deformation increases. Sensibilities to cracking of structures are changed by their different strain resistances and become stronger from bolt-shotcrete shaft, bolt-shotcrete tunnel, and brick-concrete building to brick wall. Based on distribution characteristics of cracks and wave velocity in rock masses, the overlaying strata affected by underground mining can be divided into four zones: broken zone, broken transition zone, crack generation zone, and micro deformation zone.  相似文献   

无人艇载水陆一体化测量系统集成优化技术          下载免费PDF全文

洪在地  刘斌 《海洋测绘》2020,40(6):39-42

为提高水陆一体化测量系统的作业精度和性能,开展无人艇载水陆一体化测量系统集成优化技术研究。借助仿真分析手段,对艇型及设备布置进行优化研究,并开展多传感器集成、时间同步、盲区无缝和实时拼接技术研究,设计并集成了无人艇载水陆一体化测量系统。实验表明,无人艇载水陆一体化测量系统获得的水上水下数据的平均垂直误差为0.12m。所提出的无人艇载水陆一体化测量系统集成优化技术是可行的,可为测绘艇和水陆一体化测量系统集成提供理论依据。  相似文献   

Using fast Hartley transform to study the free oscillations of the earth     

Kamal  Pratibha  Ashis Chakravarty 《Journal of Seismology》1998,2(2):179-181

In recent years, Hartley Transform (HT) as a substitute of much widely used Fourier Transform (FT) has been practised in science and industries. The advantage of faster computation of HT is enormous when one is dealing with very long data sets. One such application arises in computation of parameters of Free Oscillations of the Earth (FOE), where one needs to study very long period vibrations of the earth, excited after a large earthquake. We demonstrate here an application of HT to determine the parameters of these normal modes of the earth after the Minahasa Peninsula earthquake of 18 April 1990 (M_s = 7.5).  相似文献   

Vegetation response to climate and climatic extremes in northwest Bangladesh: a quantile regression approach     

Uddin  Mohammad Ahsan  Kamal  A. S. M. Maksud  Shahid  Shamsuddin 《Theoretical and Applied Climatology》2022,148(3-4):985-1003

Theoretical and Applied Climatology - The present study assessed the vegetation response to climate in the water-stressed northwest Bangladesh (NWB). The quantile regression analysis was employed...  相似文献   

Numerical simulation of fabric anisotropy and strain localization of sand under simple shear     

Omar Al Hattamleh  B. Muhunthan  Faisal Shalabi 《国际地质力学数值与分析法杂志》2009,33(9):1255-1275

This paper studies the effects of initial fabric anisotropy of dry sand in simple shear deformation. The effects of anisotropy are taken into consideration through the modification of the mobilized friction in the Mohr–Coulomb‐type yield surface as a function of a fabric parameter. In addition, the constitutive model uses a gradient term that directly incorporates the effects of material length scale. The constitutive formulation is implemented into ABAQUS finite element code and used to simulate shearing of the dry sand under various conditions of simple shear. The numerical simulations show that while the shear stress response is affected by fabric anisotropy, its effects on strain localization in simple shear are minimal. This is in contrast to other devices such as the biaxial shear. The strain localization in simple shear is controlled more by the imposed boundary conditions. The use of material length scale is shown to remove the effects of strain localization in the shearing response. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Fluid-induced dissolution breakdown of monazite from Tso Morari complex,NW Himalayas: evidence for immobility of trace elements     

Dewashish Upadhyay  Kamal Lochan Pruseth 《Contributions to Mineralogy and Petrology》2012,164(2):303-316

Primary igneous monazite from the Polokongka La granite of the Tso Morari complex in the western Himalayas has been partially replaced by a three-layered corona of metamorphic fluor-apatite, allanite + U- and Th-bearing phases (huttonite + brabantite), and epidote. The alteration is related to high-pressure amphibolite-facies (10–11 kbar and 587–695 °C) fluid-induced retrogression of the ultra-high-pressure granite during exhumation after India–Asia collision. The corona textures can be explained by pseudomorphic partial replacement of the original monazite to apatite and allanite via a fluid-mediated coupled dissolution–reprecipitation process. Mass balance calculations using the volume proportions and compositions of coronal minerals show that the REE, U, Th, Pb, Ba and P were conserved and not transported outside the alteration corona. The formation of fluor-apatite, allanite, huttonite and coffinite from monazite and the immobility of REE, U and Th require an influx of alkali- and F-bearing, Ca-rich fluid having high Ca/Na into the corona. We are aware of only two other occurrences of such alteration textures, and these have several similarities in terms of geodynamic setting and P–T histories of the host rocks. We suggest that there may be a common mechanism of exhumation style, and source and composition of fluids during retrogression of granitoid rocks in collisional orogens and that such breakdown textures can be used to identify metagranites that have experienced high-P metamorphism in continental collision zones, which is otherwise difficult to constrain due to the high variance of the mineral assemblages in these rocks.  相似文献   

Composition, age, and origin of the ~620?Ma Humr Akarim and Humrat Mukbid A-type granites: no evidence for pre-Neoproterozoic basement in the Eastern Desert, Egypt     

Kamal A. Ali  Abdel-Kader M. Moghazi  Ayman E. Maurice  Sayed A. Omar  Qiang Wang  Simon A. Wilde  Ewais M. Moussa  William I. Manton  Robert J. Stern 《International Journal of Earth Sciences》2012,101(7):1705-1722

The Humr Akarim and Humrat Mukbid plutons, in the central Eastern Desert of Egypt, are late Neoproterozoic post-collisional alkaline A-type granites. Humr Akarim and Humrat Mukbid plutonic rocks consist of subsolvus alkali granites and a subordinate roof facies of albite granite, which hosts greisen and Sn–Mo-mineralized quartz veins; textural and field evidence strongly suggest the presence of late magmatic F-rich fluids. The granites are Si-alkali rich, Mg–Ca–Ti poor with high Rb/Sr (20–123), and low K/Rb (27–65). They are enriched in high field strength elements (e.g., Nb, Ta, Zr, Y, U, Th) and heavy rare earth elements (La _n /Yb _n ?=?0.27–0.95) and exhibit significant tetrad effects in REE patterns. These geochemical attributes indicate that granite trace element distribution was controlled by crystal fractionation as well as interaction with fluorine-rich magmatic fluids. U–Pb SHRIMP zircon dating indicates an age of ~630–620?Ma but with abundant evidence that zircons were affected by late corrosive fluids (e.g., discordance, high common Pb). εNd at 620?Ma ranges from +3.4 to +6.8 (mean?=?+5.0) for Humr Akarim granitic rocks and from +4.8 to +7.5 (mean?=?+5.8) for Humrat Mukbid granitic rocks. Some slightly older zircons (~740?Ma, 703?Ma) may have been inherited from older granites in the region. Our U–Pb zircon data and Nd isotope results indicate a juvenile magma source of Neoproterozoic age like that responsible for forming most other ANS crust and refute previous conclusions that pre-Neoproterozoic continental crust was involved in the generation of the studied granites.  相似文献